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bioRxiv · 10.1101/2021.01.14.426658

Identifying priority areas for research and conservation of the largetooth sawfish Pristis pristis in Colombia and Panama

Abstract

Sawfishes are considered one of the most endangered families of fishes in the world. Their diadromous ecology and vulnerability to fishing nets have brought most populations to the brink of collapse. Conservation of the surviving populations is hindered by the paucity of historic and contemporary catch and observational records, and assessments of suitable coastal and riverine habitats. Colombia and Panama are two of 14 countries considered as a high priority for the development of species-specific national legal protection of the critically endangered largetooth sawfish (Pristis pristis). To construct a baseline for the temporal and spatial distribution of the largetooth sawfish in Colombia and Panama, we collected historical records from museum databases and from literature over the past century, analysed available small-scale fisheries landings databases, and conducted interviews with fish workers in 38 locations across both countries. We found 257 records of sawfish occurrences across both countries between 1896 and 2015, with 69% of the records before the year 2000. The declining trend in the frequency of observations was corroborated by fishers, who reported fewer sawfish catches over the last 20 years. Using kernel density estimation of recent encounter locations, we identify potential hotspots that may represent extant populations of sawfish. These locations are broadly characterized by their remoteness and high mangrove forest cover. Given the length and cultural diversity of the Pacific coastlines of Colombia and Panama, and the inaccessibility of many of the communities, our findings provide important guidance to target rapid conservation and fisheries interventions to priority areas. We suggest that the relative success of community-managed fishing areas in the region makes this a valuable platform on which to build local stewardship of marine resources, while raising awareness of the need to safeguard critically endangered largetooth sawfish.

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BibTeXRIS

Lopez Angarita, J., Cubillos-M, J. C., Villate-Moreno, M., Del Cid, A., Diaz, J. M., Cooke, R. G., Tilley, A.. 2021-01-17. Identifying priority areas for research and conservation of the largetooth sawfish Pristis pristis in Colombia and Panama. https://doi.org/10.1101/2021.01.14.426658

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